50 lines
1.0 KiB
TypeScript
50 lines
1.0 KiB
TypeScript
|
export type SpatialMixOptions = {
|
||
|
|
dx: number;
|
||
|
|
dy: number;
|
||
|
|
range: number;
|
||
|
|
baseGain?: number;
|
||
|
|
nearFieldDistance?: number;
|
||
|
|
nearFieldGain?: number;
|
||
|
|
nearFieldCenterPan?: boolean;
|
||
|
|
};
|
||
|
|
|
||
|
|
export type SpatialMixResult = {
|
||
|
|
distance: number;
|
||
|
|
gain: number;
|
||
|
|
pan: number;
|
||
|
|
};
|
||
|
|
|
||
|
|
export function resolveSpatialMix(options: SpatialMixOptions): SpatialMixResult | null {
|
||
|
|
const {
|
||
|
|
dx,
|
||
|
|
dy,
|
||
|
|
range,
|
||
|
|
baseGain = 1,
|
||
|
|
nearFieldDistance,
|
||
|
|
nearFieldGain = 1,
|
||
|
|
nearFieldCenterPan = false,
|
||
|
|
} = options;
|
||
|
|
if (!(range > 0)) {
|
||
|
|
return null;
|
||
|
|
}
|
||
|
|
|
||
|
|
const distance = Math.hypot(dx, dy);
|
||
|
|
if (distance > range) {
|
||
|
|
return null;
|
||
|
|
}
|
||
|
|
|
||
|
|
const volumeRatio = Math.max(0, 1 - distance / range);
|
||
|
|
let gain = baseGain * Math.pow(volumeRatio, 2);
|
||
|
|
const clampedX = Math.max(-range, Math.min(range, dx));
|
||
|
|
let pan = Math.sin((clampedX / range) * (Math.PI / 2));
|
||
|
|
|
||
|
|
if (nearFieldDistance !== undefined && distance < nearFieldDistance) {
|
||
|
|
gain = baseGain * nearFieldGain;
|
||
|
|
if (nearFieldCenterPan) {
|
||
|
|
pan = 0;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
return { distance, gain, pan };
|
||
|
|
}
|